Table 4.

Risk-of-bias summary using the revised version of the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool.

Study	Risk of bias					Applicability concerns
	Patient selection	Index test	Reference standard	Flow and timing	Patient selection		Index test	Reference standard
Poote et al [19]	+a	+	−b	?c	?		+	?
Semigran et al [14]	+	+	?	+	?		+	?
Semigran et al [15]	?	+	?	?	?		+	+
Verzantvoort et al [26]	?	+	?	−	+		+	+
Berry et al [16]d	+	?	−	?	+		?	+
Gilbert et al [17]	+	?	+	+	+		?	+
Hill et al [22]	+	−	+	?	+		?	+
Yu et al [27]	−	+	?	?	+		+	+
Ceney et al [21]	+	+	+	?	+		+	+
Chan et al [25]	?	+	+	?	+		+	+
Delshad et al [18]	?	?	+	?	+		+	+
Gilbert et al [23]	+	?	?	+	+		+	+
Trivedi et al [24]	?	?	+	?	?		?	+
Dickson et al [20]	−	+	+	?	?		+	+

^a+: low risk of bias.

^b−: high risk of bias.

^c?: unclear risk of bias.

^dIn this study, the reference standard for the triage accuracy and the reference standard for the diagnostic accuracy were different. Only the one for the triage accuracy had a high risk of bias.